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Water repellency of superhydrophobic protective film is of great interest to anti-corrosion of metallic materials due to its reduced contact area with water containing aggressive ions and self-cleaning effect. In this study, a facile electrochemical method was presented for preparing superhydrophobic film with excellent anti-corrosion and self-cleaning properties on Al alloy. The superhydrophobic film comprised nickel–cobalt phosphate (NiCoPO) with a hierarchical micro-nano structure and stearic acid (STA) with low surface energy, while the NiCoPO provides an appropriate roughness and STA offers an inert chemical state. As expected, the superhydrophobic film of NiCoPO/STA on Al alloy demonstrates a champion water contact angle of 163º and corrosion protection efficiency of 97.38%. Moreover, the water flow impact-bounce and abrasion measurements on the NiCoPO/STA surface demonstrate that the superhydrophobic film possesses decent mechanical durability. This facile electrochemical deposition method paves a universal pathway to fabricate superhydrophobic protective film with remarkable anti-corrosion and self-cleaning performance on metallic substrates. [ABSTRACT FROM AUTHOR]

In wide-bandgap semiconductor power device packaging, die bonding refers to attaching the die to substrate. Thereby, the process temperature of Ag sintering for the die bonding should be low to prevent damage to fragile dies. Herein, an organic-free strategy using Ag nanostructures derived from the thermal decomposition of metal–organic decomposition (MOD) was proposed to achieve low-temperature bonding. Significant effects on bonding performance were determined by the thermal decomposition temperature, which in turn determined the organic content and sintering degree of Ag nanostructures. At a low thermal decomposition temperature of 160 °C, incomplete decomposition resulted in high organic content in the Ag nanostructures, causing large pores inside the Ag joints owing to the generation of gaseous products. Owing to the Ag particles with naked surfaces and wide size distribution, the Ag nanostructure obtained at 180 °C showed an excellent bonding performance, resulting in a high shear strength of 31.1 MPa at a low bonding temperature of 160 °C. As the thermal decomposition temperature was 200 °C, sintering among Ag particles increased the particle size, resulting in a reduction of surface energy and driving force for sintering. We think that uncovering this underlying mechanism responsible for the bonding performance will promote the application of Ag MOD in the die bonding of WBG power devices. [ABSTRACT FROM AUTHOR]

The abnormal grain growth of high-purity cobalt during high-temperature annealing was analyzed in this work. The microstructure and orientation evolutions were characterized using the in situ electron backscatter diffraction technique. It was found that the HCP ↔ FCC phase transformation follows the orientation relationships of {0001}HCP//{111}FCC, < 11–20 > HCP// < 1–10 > FCC during both the heating and cooling process. At around 500 °C, the {100} oriented FCC grains exhibited abnormal growth, with the size exceeding 300 μm. The origin of this phenomenon was analyzed from the perspectives of grain orientation distribution and surface energy. The growth of {111} oriented grains is inhibited by the {111} texture, leading to the abnormal growth of {100} oriented grains, which have the second lowest surface energy. Additionally, the transformation microstructure of the abnormally large grains after cooling is analyzed. This work provides insights into the microstructure stability of high-purity cobalt sputtering targets during their service. [ABSTRACT FROM AUTHOR]

In this paper the size- and shape dependences of 8 different integral and partial molar thermodynamic quantities are derived for solid and liquid nano-phases, starting from the fundamental equation of Gibbs: i) The integral molar Gibbs energies of nano-phases and the partial molar Gibbs energies of components in those nano-phases, ii) The integral molar enthalpies of nano-phases and the partial molar enthalpies of components in those nano-phases, iii) The integral molar entropies of nano-phases and the partial molar entropies of components in those nano-phases, and iv). The integral molar inner energies of nano-phases and the partial molar inner energies of components in those nano-phases. All these 8 functions are found proportional to the specific surface area of the phase, defined as the ratio of its surface area to its volume. The equations for specific surface areas of phases of different shapes are different, but all of them are inversely proportional to the characteristic size of the phase, such as the diameter of a nano-sphere, the side-length of a nano-cube or the thickness of a thin film. Therefore, the deviations of all properties discussed here from their macroscopic values are inversely proportional to their characteristic sizes. The 8 equations derived in this paper follow strict derivations from the fundamental equation of Gibbs. Only the temperature dependent surface energy of solids and surface tension of liquids will be considered as model equations to simplify the final resulting equations. The theoretical equations are validated for the molar Gibbs energy against the experimental values of liquidus temperatures of pure lead. The theoretical equations for the molar enthalpy are validated i). Against the experimental values of dissolution enthalpy differences between nano- and macro cobalt particles in the same liquid alloy and ii). Against the size dependent melting enthalpy of nano-indium particles. In this way, also the theoretical equations for the molar entropy and molar inner energy are validated as they are closely related to the validated equations for the molar Gibbs energy and molar enthalpy. [ABSTRACT FROM AUTHOR]

This work presented a novel method for fabricating corrosion-resistant and fluorine-free superhydrophobic Al2O3/nickel hydroxide (NiOxHy)/stearic acid (STA) composite coating on the Al alloys. The Al2O3/NiOxHy composite film with an ideal micro-nanostructure was assembled on Al alloys by a one-step anodizing method. This facile and low-cost technique for fabricating superhydrophobic coating includes high-temperature anodizing in oxalic acid aqueous solution with Ni2+ and subsequent spin coating of the STA layer. The superhydrophobicity of as-fabricated film results from the hierarchical micro-nanostructure of Al2O3/NiOxHy and the coverage of STA with low surface energy, while the micro-nanostructure is beneficial to providing the appropriate roughness and maintaining more STA in its interstices and surface. The Al alloys with an optimal superhydrophobic coating displayed a static water contact angle of 164°, excellent self-cleaning ability, and superb corrosion-resistant efficiency of 99.6%. This facile method offers an effective strategy to fabricate corrosion-resistant protective coating on metallic substrates, which can significantly prolong the working lifetime of metallic materials in harsh environments. [ABSTRACT FROM AUTHOR]

The special wettability of superhydrophobic aluminum alloys has a broad applied foreground in important industrial fields, such as aviation, automobiles, and ships. However, the microstructures of superhydrophobic surfaces are easily destroyed, causing them to lose superhydrophobicity, which seriously restricts the application of superhydrophobic surfaces. To solve this problem, we developed a simple and low-cost fabrication method by the blasting and chemical deposition of Ni and P to process robust micro/nano-composite structures on an aluminum alloy material and then obtained a superhydrophobic nickel–phosphorus–aluminum surface (SHP-NiP-Al) with a water contact angle of 163° and a water rolling angle of 3° through low surface energy modification. The prepared SHP-NiP-Al had an excellent self-cleaning performance and antifouling property. In addition, it showed great mechanical robustness and chemical stability performance in the sand impact, blade scratch, and acid/base solution tests. It also demonstrated good corrosion resistance performance. Electrochemical corrosion tests indicated that the corrosion resistance of SHP-NiP-Al was better than that of the original aluminum. Moreover, SHP-NiP-Al could collect the water from the fog environment. This method is helpful for the practical use of superhydrophobic aluminum alloy surfaces. [ABSTRACT FROM AUTHOR]

A Cu coating was introduced on the steel surface by electroplating, and the wetting and spreading behavior of Mg alloys on Cu-coated steel substrates during the laser machining process was investigated. Wetting behavior, microstructure, diffusion kinetics, and thermodynamic calculations were conducted to comprehend the role of the Cu coating in the wetting process. The contact angle decreases first followed by an increase with the increased Cu coating thickness. The interfacial reaction is enhanced by the combination of Mg atoms with Fe atoms, transitioning the primary wetting mechanism from reaction control to adsorption/desorption processes. The introduction of Cu elements promoted the creation of a loosely structured Mg + Mg2Cu phase at the solid–liquid interface between Mg and steel. It significantly increased the wetting of Mg droplets on the steel surface. The results showed that the wetting behavior in this material system was synergistically governed by reactions, surface energy, and thermodynamic driving forces. These findings provided a foundational understanding for enhancing the joining of dissimilar Mg/steel materials under non-isothermal processing conditions. [ABSTRACT FROM AUTHOR]

The more and more oily sewage from industry, shipping and domestic life greatly threaten our life and health. In this work, the porous Co–Ni(OH)2/Ni foam composites were prepared by a simple hydrothermal method and subsequent annealing at 200 °C. The high surface energy and novel structure of nanocone array endowed the composite with superhydrophilicity and superoleophobicity. After the surface modification of stearic acid (STA) with low surface energy, the Co–Ni(OH)2/Ni@STA composites were endowed with superlipophilicity and superhydrophobicity due to the low surface energy of STA and special surface nanostructure. Meantime, two extreme wetting states can be switched by alternating 200 °C calcination and STA surface modification. And the doping of Co element endows the composites with the excellent corrosion resistance. Based on the controllable switchable wetting performance of Co–Ni(OH)2/Ni composite, a three-way T-tube was designed for oil–water separation. Whether it is heavy oil or light oil, the device has high separation efficiency and excellent cyclic stability. [ABSTRACT FROM AUTHOR]

Nature-inspired hydrophobic coatings have caught great attention due to their repellency to corrosive mediums and less interaction between substrate and chemical species. Aluminum is considered one of the metals having superior properties against corrosion due to passive film formation. It can further be enhanced by the formation of a hierarchical structure through 2nd step anodization. In previous studies, carbon infiltrated in anodized alumina pores through CVD method (chemical vapor deposition) was quite an expensive and complex method. The fabrication of anti-corrosion coating with a simple and cost-effective method will broaden the aluminum alloy applications in the chemical, petrochemical, and aerospace industries, etc. In this research, pyrolytic carbon is infiltrated in porous alumina through pyrolysis at three different temperatures for 30 min under a controlled environment by using flaxseed oil as a source of carbon. The surface morphology along with chemical composition and wetting angle were studied through SEM (Scanning Electron Microscope), EDX (Energy Dispersive X-ray Spectroscopy), and Sessile drop method. It was found that both low surface energy and high roughness participate in increasing the wetting angle. Nanocomposite coating having maximum carbon content has a maximum wetting angle with inorganic liquid. Based on the electrochemical behavior determined by Tafel and EIS (Electrochemical Impedance Spectroscopy) analysis, the hydrophobic coating containing 57.5% carbon content having a contact angle of 95° exhibits maximum corrosion resistance of around 28,000 kohm as compared to anodized aluminum having minimum corrosion resistance of around 4.26 kohm. The results and the cost-effective method could be beneficial in aircraft parts as well as in aeronautical applications. [ABSTRACT FROM AUTHOR]

Superhydrophobic cotton fabric was prepared by coating fluorine-free cationic polyhedral oligomeric siloxane/polydimethylsiloxane-modified polyacrylate emulsion using the pad-bath method. Due to the successful introduction of heptaoctylmethacryloxypropyl polyhedral oligomeric siloxane and monovinyl polydimethylsiloxane, the film with a rough structure and low surface energy was formed on the cotton fabric surface, exhibiting excellent superhydrophobicity with a water contact angle of 161°. Additionally, the finished cotton fabric showed exceptional self-cleaning and anti-foiling abilities. The finished cotton fabric had a separation efficiency of over 97% for oil–water mixtures and maintained a high separation efficiency of over 96% after 20 cycles of separating the n-hexane/water mixture. In addition, the separation of different water-in-oil emulsions was achieved by overlapping three layers of finished cotton fabric. This suggests that the as-prepared superhydrophobic cotton fabric will be a promising material in application for treating oil–water mixtures and water-in-oil emulsions due to the low-cost, simple fabrication method and the superior separation capabilities. [ABSTRACT FROM AUTHOR]

A low-carbon bainitic steel serving for the high-speed train was jointed with the laser–arc hybrid welding, and the low-temperature (−40 °C) impact toughness of the joint was evaluated. The results showed that the microstructure of each micro-zone of the welded joint was mainly bainite, but the morphology and size were quite different. The average grain size of the weld material (WM) was 1.69 μm, which was 19% finer than the base material (BM). At the same time, there was a small amount of martensite-austenite (M-A) constituent at the grain boundary, which led to the microhardness of the WM being higher than that of the BM, up to 293.6 HV, about 1.13 times that of the BM. The low-temperature impact toughness of each micro-zone of the welded joint from high to low was 64 J in the inter-critical heat-affected zone, 50 J in the BM, 49 J in the WM, and 43 J in the coarse grain heat-affected zone. The difference in impact toughness was due to the difference in the content of high-angle grain boundaries and the size of the M-A constituent in each region. The larger the size of the M-A constituent, the easier it was to cause stress concentration and produced micro-cracks, which reduced the impact performance. The high-angle grain boundary holding a low surface energy resulted in the crack propagating along the grain boundary. Therefore, the higher the content of high-angle grain boundaries, the more tortuous the crack propagating path and the better the impact performance. [ABSTRACT FROM AUTHOR]

The surface structures and relative stabilities of low-miller-index surfaces of γ-TiH and γ-TiH2 have been investigated as a direct function of environmental conditions (hydrogen partial pressure pH2 and temperature T), using the first-principles thermodynamic calculations. The results were used to construct the surface phase diagrams for a wide pH2 range at T = 300 and 900 K. The γ-TiH surfaces tend to be dominated by the non-stoichiometric (110) at low pH2 values, and the most energy-favored surface termination would change from the 110-ns-2Ti1H to the 110-ns-2Ti2H and then to the 110-ns-2Ti4H as pH2 increases. For pH2 > e−43.6 at 300 K (or pH2 > e−2.5 at 900 K), γ-TiH can no longer be stable but have the tendency to transform into γ-TiH2, by consistently absorbing H from the gaseous environment. The γ-TiH2 surfaces tend to be dominated by the stoichiometric (111) facet with the 111-stoi-2H termination and with a surface energy of 1.31 J/m2. [ABSTRACT FROM AUTHOR]

Transition metals (TMs) have an excellent catalytic effect on the thermal decomposition of ammonium perchlorate (AP). However, nanosized TM catalysts tend to agglomerate due to their high surface energy and magnetism. In this work, a new Fe/Al composite catalyst was synthesized by loading Fe nanoparticles onto Al powder through a facile replacement route, and its effect on the thermal decomposition stability of AP and AP-based propellants was investigated. Morphological and structural characterization showed that Fe nanoparticles were successfully decorated on the Al surface without noticeable aggregation or shedding. The diameter of Fe nanoparticles was approximately 10 nm. The constructed Fe/Al composite catalyst presented a strawberry-like structure. Elemental mapping analysis revealed that the dispersion state of the Fe/Al composite catalyst was better than that of commercial Fe nanoparticles with AP. Thermal analysis indicated that the Fe/Al composite catalyst presented excellent catalytic stability in the high-temperature decomposition (HTD) of AP, reducing the HTD temperature by approximately 100 °C. Burning tests showed that the relative standard deviations of the burning rate with the Fe/Al composite catalyst were 2.5 and 2.2% at 5 and 10 MPa, respectively, whereas those with Fe reached 17.1 and 13.9% at 5 and 10 MPa, respectively. The Fe/Al composite catalyst inherited the good dispersion of Al, effectively resolving the problems of Fe nanocatalyst agglomeration. Therefore, the as-obtained Fe/Al composite catalyst can significantly improve the thermal decomposition stability of AP and AP-based propellants and will have wide application prospects in the field of AP-based propellants. [ABSTRACT FROM AUTHOR]

Aluminum (Al) is often used for aircraft, shipbuilding, automobile and other related fields because of its low density, high strength, and low cost. However, the Al has the limitation in the practical application because of the easily corroded, poor chemical stability, and difficult to remove contaminants, which seriously affects the wider application of Al. To address these limitations, we develop a simple, non-fluorinated, and low-cost method to obtain the lubricant-impregnated aluminum surface (SLIPS-Al). We first put the cut Al sheet into the solution containing zinc, and then heating oxidation to obtain the micro/nano-scale rough structures. Next, the oxidized sample was modified with low surface energy to achieve the superhydrophobic Al, and then, silicone oil was uniformly dropped on the superhydrophobic surface to obtain the SLIPS-Al. The liquids could slide off SLIPS-Al surfaces and exhibited excellent self-cleaning performance. Next, the silicone oil shear force, abrasion, water impact, acid corrosion, alkali corrosion, simulated seawater corrosion, and natural environment placement tests showed that the SLIPS-Al had excellent surface robustness and chemical stability. Furthermore, the SLIPS-Al had an anti-icing ability and a lower de-icing power compared with the Origin Al. Anti-corrosion test showed that the SLIPS-Al had an excellent anti-corrosion than the Origin Al. The SLIPS-Al with the excellent performances has a good prospect for practical engineering application. [ABSTRACT FROM AUTHOR]

Hexafluorides associated with polymers are a growing alternative to chromium-VI metal treatments. The polymers in these conversions enhance both the adhesion of the coating and the corrosion protection. The underlying mechanisms involve chemical bonding and surface interactions, the latter being readily accessible by measuring surface energy. We here investigate the link between surface energy, paint adhesion and corrosion resistance of painted aluminium panels. We evaluate zirconium hexafluorides conversion coatings with and without co-polymers made of acrylic acid and phosphonate or phosphate groups using an automated measurement of oil/solvent/metal contact angles. First, experimental results highlight that increased aluminium surface energies correlate with improved paint adhesion while limited corrosion seems related to low polar surface energies. Given this critical role of surface energy in these performances, the balance between adhesion and corrosion can be optimized by targeting specific values of contact angles of water and di-iodomethane. Second, the addition of polymer to hexafluoride treatments increases the polar surface energy and gives higher performances in corrosion and paint adhesion. Besides, a kinetic study reveals that the addition of polymer in zirconium conversions slows down the surface ageing over several days and allows a delayed paint application. Finally, as highlighted by the addition of phosphate or phosphonate functions in polyacrylic-acid polymers, the balance between adhesion and corrosion is improved by decreasing the polymer hydrophilicity to avoid corrosion while maintaining a sufficient functional density in its structure to develop covalent bonds with paint. This insight from contact angles and screening possibilities may contribute to speeding-up the development of new polymer chemistries in conversion technologies. [ABSTRACT FROM AUTHOR]

High hydrophobicity and environmental adaptability are the key performance indicators for the application of fly ash (FA) as waterproof filling material in landfill and building engineering. However, the current hydrophobic modification of fly ash is mainly based on the simple mixing or coating of hydrophobic agent and adhesive. This physical adsorption hydrophobic modification method based on weak intermolecular force such as van der Waals force will lead to poor hydrophobic stability and environmental adaptability. In this study, a preparation method of superhydrophobic FA with micro–nano-hierarchy roughness by coupling polydimethylsiloxane (PDMS) and FA through siloxane covalent bond (–Si–O–Si–) under the action of catalyst and mechanical external force was explored for the first time, and the microstructure, chemical properties and wettability of FA and superhydrophobic FA were characterized. The environmental resistance of superhydrophobic FA, such as acid and alkali resistance, high temperature resistance and ultraviolet resistance, were evaluated. The results show that PDMS is successfully grafted to the surface of FA particles by means of Si–O–Si covalent bond, and the mechanical external force gives the superhydrophobic FA greater micro–nano-roughness. The combination of low surface energy and micro-roughness successfully changes the FA from superhydrophilic to superhydrophobic, where the water contact angle (WCA) increases from 21° to 155°, and the water sliding angle (WSA) reaches 8°. The robustness of acid and alkali resistance, high temperature and ultraviolet resistance show that superhydrophobic FA has good environmental tolerance. A preparation method of superhydrophobic fly ash which can endow fly ash with low surface energy and micro–nano-roughness is proposed for the first time. PDMS was grafted onto the surface of fly ash particles by siloxane covalent bond. The super hydrophobic fly ash obtained has good environmental adaptability. [ABSTRACT FROM AUTHOR]

High thermal conductivity graphite films (GFs) have been widely used in the field of heat dissipation. However, due to their extremely smooth surface and low surface energy, it is difficult for them to be used as the reinforcement of composites. In this study, hexagonal pits and channels were prepared on the surface of GFs by high-temperature air etching treatments. The morphology and reason of pits and channels prepared in the air were investigated. The pits and channels enable the mechanical interlocking effect between the GFs and the carbon matrix and enhance the mechanical and thermal properties of the carbon/carbon (C/C) composites. The GFs-reinforced C/C composites with high thermal conductivity were fabricated through impregnation-carbonization cycles. The results show that, with the increase in etched GFs volume fraction, the horizontal thermal conductivity was increased from 148 to 412 W/(m K). Moreover, compared with pristine GFs-reinforced C/C composites, etched GFs-reinforced C/C composites show an increase of 165% in flexural strength. Overall, etched GFs-reinforced C/C composites with superior properties have a broad prospect in the fields of heat dissipation. [ABSTRACT FROM AUTHOR]

Potentiostatic deposition of cobalt film and cobalt-graphene, Co-G, composite, followed by modification with low surface energy stearic acid (SA), was used to fabricate superhydrophobic films on a steel substrate successfully. A scanning electron microscope was used to analyze the surface morphology of the prepared superhydrophobic cobalt film modified by stearic acid, Co-SA, and the cobalt-graphene film modified by stearic acid, Co-G-SA. The findings show that both the fabricated films have micro-nanostructures. The Co-G-SA film shows a higher roughness due to the network structures of graphene and so exhibits higher superhydrophobicity. The Fourier transform infrared spectrophotometer, FTIR, results confirm the formation of Co-SA and Co-G-SA films on the steel surface. The wettability of the prepared films shows that they exhibit superhydrophobicity, where the Co-SA and Co-G-SA films have contact angles of 155° and 158°, respectively. The Potentiodynamic polarization results show that the value of the corrosion current density for steel coated with Co-SA (0.7094 µA) is lower than that of bare steel (0.1457 mA), while the coated steel with Co-G-SA film has the lowest value (0.1732 µA). The electrochemical impedance spectroscopy, EIS, results show that the charge transfer resistance for steel coated with Co-SA is 38 times that of bare steel, while steel coated with Co-SA is 57 times that of bare steel. Potentiodynamic polarization and EIS results show that the prepared Co-G-SA film superhydrophobic films exhibit higher corrosion resistance. Co-G-SA film has higher mechanical stability (maintains superhydrophobicity until 900 abrasion cycles), chemical stability (has superhydrophobicity in the pH range 1–13), and long-term stability (retains superhydrophobicity after 30 days in a 0.5 M NaCl solution) in 0.5 M NaCl solution. [ABSTRACT FROM AUTHOR]

A new high-precision angular-dependent potential of the Ni–Pd system was obtained by fitting the experimental data and first-principles calculations. Then, the element segregation characteristics and thermal stability of Ni–Pd bimetallic nanoparticles were investigated by Monte Carlo method and molecular dynamics method. The results show that the chemical ordering pattern of PdxNi1 − x nanoparticle is the result of the competition of surface energy, strain energy, bond energy and interface energy. When a small amount of Pd atoms are substitutionally doped into the Ni nanoparticle, all the Pd atoms will be segregated on the surface and dispersed. The synergistic effect of Ni atoms and Pd atoms in the surface will improve the catalytic activity and carbon deposition resistance of PdxNi1 − x nanoparticle catalyst in methane dry reforming reaction. Increasing the doping amount of Pd atoms will gradually reduce the melting point of PdxNi1 − x nanoparticle, thereby reducing its sintering resistance. [ABSTRACT FROM AUTHOR]

The separators have an impact on the performance of lithium-based battery, whereas traditional polyolefin separators are hard to retain enough liquid electrolyte for its nonpolar surface and lead to battery performance degradation. In this experimental work, we have tried to activate polyethylene (PE) separator by γ-ray irradiation with different doses. According to these results of FTIR-ATR, the contact angle and mechanical test, it is concluded that γ-ray irradiation would get the PE long chains broken and oxidized furtherly. Therefore, these irradiated separators show a higher surface energy and inferior mechanical strength than pristine PE separator. For comprehensive consideration, the PE-20 (irradiated by the dose of 20 kGy) separator is selected to evaluate the electrochemical performance. The LiCoO2 cells with PE-20 separators have a better cyclic stability than that of PE separator for lower interfacial resistance and stronger affinity to liquid electrolyte. Especially in the unsymmetrical rate performance test, the cells based on PE-20 separator have higher discharge capacity. It demonstrates that this method of γ-ray irradiation could be used to modify PE separator for enhancing battery performance. [ABSTRACT FROM AUTHOR]

In this study, wood plastic composites (WPC) made of poly(lactic acid) PLA and a bark-filler were manufactured. Two degrees of bark comminution (10–35 mesh and over 35 mesh) and varied content of bark (40, 50 and 60%) were investigated. The studied panels were compared with analogically manufactured HDPE boards. The manufacture of composites involved two stages: at first, WPC granules with the appropriate formulation were produced using the extruder (temperatures in individual extruder sections were 170–180 °C) and crushing using a hammer mill after cooling the extruded composite; secondly, the obtained granulate was used to produce boards with nominal dimensions of 300 × 300 × 2.5 mm3 by flat pressing in a mold, using a single daylight press at a temperature 200 °C. The study proved that comminuted bark can be applied as a filler in PLA composites. However, an increase in bark content decreased mechanical properties (MOR, MOE) and deteriorated humidity resistance (high TS and WA) of the panels. Along with the increase in bark content, an increase in the contact angle of the composite surfaces and a decrease in the total surface energy were noted. It was also found that PLA composites have higher strength parameters and lower moisture resistance compared to HDPE composites with the same bark content. [ABSTRACT FROM AUTHOR]

Local curvatures have a profound influence on sintered microstructure. Here, using phase-field simulations, particle curvature effects were phenomenologically investigated by using geometrical configurations of two, three, and four particles, and by systematically varying particle curvatures. Some geometries, involving two, three and four particles, exhibited the expected smooth neck-length evolution, where the maximum neck length was determined by grain boundary (GB) energy ( γ GB ) rather than surface energy ( γ S ). In contrast, triangular arrangement of particles with unequal radii manifested a secondary necking event in form of a step during neck evolution. The secondary necking event coincided with internal pore collapse, and only specific range of particle radius ratios manifested such a mechanism. γ S played a dominant role in triggering the secondary necking event, while γ GB determined the remnant microstructure. Broadly, the geometries employed here allow us to computationally examine the sintering of particles that display wide variation in shapes and size distributions. [ABSTRACT FROM AUTHOR]

The superhydrophobic surface was prepared on biomedical Ti–6Al–4V alloy by hydrothermal treatment coupled with subsequent hydrophobic treatment. The surface morphologies, surface roughness, phase and elemental compositions, water contact angle and hemocompatibility of the superhydrophobic samples were investigated. The results show that the hydrothermally treated sample is mainly composed of Na2Ti6O13 phase with some –OH groups. The surface morphologies of the hydrothermally treated samples change from feather-like structure to grass-like structure, and the surface roughness gradually increases with increasing the concentrations of NaOH solution. After hydrophobic treatment, the surface roughness of samples slightly decreases, and the water contact angles increase first, reaching the maximum value of 159.24° ± 1.89° at 3.75 mol/L, and then decrease with increasing the NaOH concentrations. The –C8H4F13 low surface energy fluorides are grafted onto the surface of hydrothermally treated sample by a self-assembly dehydration reaction, resulting in the formation of the superhydrophobic surface. The superhydrophobic surface effectively decreases the hemolysis ratio and platelets adhesion, and prolongs the dynamic coagulation time, indicating that it greatly improves the hemocompatibility of the biomedical Ti–6Al–4V alloy. [ABSTRACT FROM AUTHOR]

Artificial superhydrophobic coatings with various properties have been developed by regulating surface chemical compositions and rough microstructures. Herein, a superhydrophobic Ni3S2 coating was fabricated on 304 stainless steel via combining electrodeposition, solvothermal reaction and chemical modification. Owing to the cooperation of the low surface energy of myristic acid, and rough structure of Ni3S2 nanorods, the coating exhibited remarkable superhydrophobicity with water contact angle (WCA) up to 163 ± 1°. The superhydrophobic coating tightly bonded with the steel substrate could withstand different mechanical damages, and the surface still maintained higher WCA after suffering from tape-peeling, sandpaper abrasion, water droplets impact and sand-flow impingement tests. In addition, the self-cleaning tests verified that the superhydrophobic coating was significantly repellent to different types of contaminations. Moreover, the Ni3S2 coating was capable of degrading methylene blue molecules under UV illumination, thereby restricting the damage of organic contaminations to the surface superhydrophobicity. It is expected that the durable and self-cleaning superhydrophobic coating will be suitable for achieving water-repellent surfaces to meet applications in harsh environments. [ABSTRACT FROM AUTHOR]

The interface properties of CeAlO3 (110)/NbC (111) were calculated by the first-principles and the refinement of CeAlO3 on NbC in hypereutectic Fe–Cr–C–Nb hardfacing alloy was demonstrated by experiments. The calculation results show that the mismatch of CeAlO3 (110)/NbC (111) is 7.2%, which indicates that the interface between CeAlO3 (110) and NbC (111) is a semi-coherent interface. Then, 11 layer CeAlO-terminated CeAlO3 (110) surface was selected to build interface with NbC (111) surface, whose surface energy is 0.380 eV/Å2. Because of the instability of O-terminated CeAlO3 (110) surface, its surface energy cannot achieve convergence. 6 kinds of interfaces between CeAlO3 (110)/NbC (111) were constructed, in which, interface-3 is the most stable with strong ionic and covalent bonds. Theoretically, CeAlO3 can act as the heterogeneous nucleation site for NbC. The experimental results show that the (Cr, Fe)7C3, NbC and γ-Fe phases exist in hypereutectic Fe–Cr–C–Nb–CeAlO3 hardfacing alloys. When CeAlO3 was added into the alloy, NbC can be refined. [ABSTRACT FROM AUTHOR]

Due to the wide application prospects in energy harvesting, conversion, and emission control technology, wettability has gathered momentum in recent years. Surface wettability alteration by nanomaterial fabrication and coating is of recent interest among researchers to attain desirable wetting surfaces. The wettability of liquid over a surface changes with surface properties such as roughness, surface energy, porosity, capillarity, and structure. Eventually, surface chemistry plays major role in changing surface energy which in turn leads to wettability alteration toward wetting and non-wetting extents. Herein, the dependence of surface properties in wettability alteration has been analyzed with the literature reports. Furthermore, surface pre- and post-treatments such as laser, ozone plasma, and UV irradiation contribute to change of surface energy inducing the liquid to encroach toward superhydrophilicity and superhydrophobicity. This review article analyzes the properties that induces wetting and non-wetting ability of liquids over surfaces. Theoretical models opted for wettability determination has been accounted to study the contribution of roughness, porosity, and surface energy. The article provides a clear idea of properties involved in wettability alteration with respect to wide range of applications in energy conversion, oil–water separation, self-cleaning, bio-adhesion, and bio-molecular immobilization. [ABSTRACT FROM AUTHOR]

In this article, a facile and efficient nanosecond laser processing method was carried out to construct a grid of microgrooves on an aluminum surface. After modification with low surface energy materials, various superhydrophobic surfaces with different water adhesion are obtained. The wetting properties of the obtained samples could be regulated by adjusting the number and line spacing (LS) of laser processing steps. The contact angle of the obtained superhydrophobic samples increased with the decrease in LS, while the sliding angle showed the opposite trend. Increasing the number of laser processing steps is beneficial to increase the contact angle and reduce the sliding angle. The wetting mechanism was analyzed to explain the cause of change in the wetting behaviors. The tribological tests showed that the surface textures of superhydrophobic samples improved their tribological properties. What is more, whether it is under dry friction or water lubrication conditions, the obtained superhydrophobic samples with large LS have good anti-friction and wear-resistant ability. The advantages of the facile preparation and excellent tribological properties will definitely expand the use of laser-machined superhydrophobic surfaces. [ABSTRACT FROM AUTHOR]

In the context of the development of materials, morphology control represents an important tool for tuning their properties, thus enabling their application on photocatalysis, energy conversion and other areas. In this work, DFT/B3LYP methodology was carried out to investigate the surface structure and the electronic, ferroelectric and magnetic properties of low index surfaces of the multiferroic PbNiO3 material at the R3c crystalline phase. The results indicate that the surface energy increases in the following the order (110) < (012) < (111) < (001) < (101) < (100). These results allow us to predict the available morphologies, finding that six theoretical morphologies correspond to those reported experimentally, while nine morphologies have not yet been reported experimentally. The properties of the exposed surfaces for each morphology can be associated with the number of oxygen vacancies (V0), and the presence of uncoordinated [NiO6] and [PbO6] clusters. [ABSTRACT FROM AUTHOR]

In this paper, two developed models for electrical conductivity of polymer nanocomposites are linked to express an equation for tunneling distance between adjacent carbon nanotubes (CNT) by the effective properties of polymer matrix, CNT, interphase and networks. The tunneling distance is calculated for some samples at different CNT concentrations. In addition, the suggested equation is applied to justify the impacts of all parameters on the tunneling distance. The tunneling distance decreases as CNT concentration increases, but its variation reduces at high CNT loading. The suggested equation demonstrates that a thick interphase, thin and short CNT, high filler concentration, poor percolation threshold, low surface energy of polymer and high CNT surface energy produce a short tunneling distance. [ABSTRACT FROM AUTHOR]

In this study, coatings of polydopamine (PDA) in the presence of caffeine were investigated upon their deposition on substrates with different surface energies. The physicochemical properties and stability of PDA coatings deposited in the absence and presence of caffeine (C/PDA) on Si/SiO2 (high surface energy), cellulose acetate butyrate (CAB) (intermediate surface energy) and polystyrene (PS) (low surface energy) surfaces were investigated by means of ellipsometry, contact angle measurements and X-ray photoelectron spectroscopy. In order to gain insight about the interactions between caffeine and PDA at molecular level, Raman and infrared (FTIR-ATR) spectroscopy measurements were performed for PDA and C/PDA, and the results were supported by density functional theory calculations. In comparison with bare PDA, the C/PDA system displayed an increase in the deposition rate on all substrates, indicating co-deposition of caffeine and PDA. PDA and C/PDA coatings turned hydrophobic substrates into hydrophilic surfaces and vice versa. PDA coatings on CAB and PS films were the most stable systems. CAB/PDA microbeads were created and tested as new adsorbents for caffeine, presenting removal capacity of 40%. [ABSTRACT FROM AUTHOR]

Increasing awareness of environmental concerns has strongly pushed the scientific community towards the search for new solutions for efficient removal of oils and organic solvents from water. Here, we report the preparation of multifunctional TiO2-coated melamine-formaldehyde (MF) sponges as absorbent material for oils and organic solvents in water. TiO2-coated MF sponges were fabricated through an environmentally friendly approach, consisting in a simple immersion of the sponge into an oleic acid-capped TiO2 nanoparticles dispersion. The adhesion of TiOle coating to the sponge was then improved by the deposition of a low surface energy diamond-like carbon (DLC) thin layer. Our results highlighted that the modified MF sponges possess superhydrophobic and oleophilic behaviour, inertness to corrosive environment, good durability and reusability. Furthermore, the superhydrophobic DLC/TiO2@sponges showed (1) novel self-cleaning properties towards an absorbed commercial organic dye (IR-270BKA, chosen as representative) under visible light irradiation and (2) enhanced flame-retardant behaviour respect to the pristine MF sponge. These findings point out an important added value of DLC/TiOle@sponges making them promising candidates for wastewater treatments. [ABSTRACT FROM AUTHOR]

Iridium thin films are grown by direct-current plasma magnetron sputtering, on MgO single-crystal substrates with various surface orientations, i.e. (100), (111), and (110). The surface morphology, the crystalline properties of the films, and the substrate–thin-film interface are investigated by atomic force microscopy, X-ray diffraction (XRD), focused ion beam scanning electron microscopy, and high-resolution transmission electron microscopy, respectively. The results reveal that hetero-epitaxial thin films with different crystallographic orientation and notable atomic scale smooth surface are obtained. From the XRD analysis, the following epitaxial relations are obtained: (1) (100)Ir||(100)MgO out-of-plane and [001]Ir||[001]MgO in-plane for Ir grown on MgO(100), (2) (110)Ir||(110)MgO out-of-plane and [1-10]Ir||[1-10]MgO in-plane for Ir grown on MgO(110), and (3) (111)Ir||(111)MgO out-of-plane and two variants for in-plane orientation [1-10]Ir||[1-10]MgO and [1-10]Ir||[10-1]MgO, respectively, for Ir grown on MgO(111). Because of the large misfit strain (9.7%), the thin films are found to grow in a strain-relaxed state with the formation of geometrical misfit dislocations with a ~ 2.8-nm spacing, whereas thermal strain is stored upon cooling down from the growth temperature (600 °C). The best structural characteristics are obtained for the (111)-oriented films with a mosaicity of 0.3° and vanishingly small lattice distortions. The (100)- and (110)-oriented films exhibit mosaicities of ~ 1.2° and lattice distortions of ~ 1% which can be explained by the larger surface energy of these planes as compared to (111). [ABSTRACT FROM AUTHOR]

By means of the CRYSTAL computer program package, first-principles calculations of polar ZrO-, Ca- and O-terminated CaZrO3 (011) surfaces were performed. Our calculation results for polar CaZrO3 (011) surfaces are compared with the previous ab initio calculation results for ABO3 perovskite (011) and (001) surfaces. From the results of our hybrid B3LYP calculations, all upper-layer atoms on the ZrO-, Ca- and O-terminated CaZrO3 (011) surfaces relax inwards. The only exception from this systematic trend is outward relaxation of the oxygen atom on the ZrO-terminated CaZrO3 (011) surface. Different ZrO, Ca and O terminations of the CaZrO3 (011) surface lead to a quite different surface energies of 3.46, 1.49, and 2.08 eV. Our calculations predict a considerable increase in the Zr–O chemical bond covalency near the CaZrO3 (011) surface, both in the directions perpendicular to the surface (0.240e) as well as in the plane (0.138e), as compared to the CaZrO3 (001) surface (0.102e) and to the bulk (0.086e). Such increase in the B–O chemical bond population from the bulk towards the (001) and especially (011) surfaces is a systematic trend in all our eight calculated ABO3 perovskites. [ABSTRACT FROM AUTHOR]

In this study, a durable, reusable, effective and large-area molding method was proposed to fabricate hierarchical structures on the CF/PEEK composite surface. The hierarchical structures were fabricated using a combination of sandblasting and anodizing treatments on the metal surface. Subsequently, a hot-pressing process was adopted for producing structures that matched the metal templates. The rough surface was modified by (Heptadecafluoro-1,1,2,2-tetradecyl)trimethoxysilane with low surface energy to obtain superhydrophobicity. Scanning electron microscopy was utilized to observe the surface morphologies and structure. The chemical composition and roughness were analyzed by FT-IR spectroscopy and the laser microscopy, respectively. Wettability was characterized through contact angle measuring instruments, and static and dynamic sliding contact angles were obtained to be 158.23° and 8.38°, respectively. After the abrasion test, the CF/PEEK composite surface still maintained reasonable mechanical stability. Comparing with the untreated sample, CF/PEEK superhydrophobic surface exhibited excellent anti-icing performance with freezing time increasing from 54 to 514 s at − 20° and icing adhesion strength reducing to 30.5 kPa. Although the fabrication of composite surface with water repellency presented here is useful for anti-icing, it can also be applied in other applications that require superhydrophobic surfaces. [ABSTRACT FROM AUTHOR]

3D reconstruction of ZnO micron ridges was carried out, and the sintering behaviors of these features were studied. Both the grain size and the relative density increase with the sintering time. The densification is through grain boundary diffusion, and the grain growth is through evaporation–condensation. The pore number in the ridges decreases with the pore size increase. Both grain boundary diffusion related flux J gb and evaporation–condensation related diffusion flux J e / c g increase with the sintering time. However, the former is five orders of magnitude lower than the latter, indicating the dominance of the grain growth process in the ridges. Pore shapes evolve from deformed round tubes, to trigonal tubes, and then to deformed flat tubes. The pore surface evolves from a saddle ridge type to saddle ridge plus saddle rut types. The decreasing dihedral angle ψ during sintering indicates increased surface energy of pores, consistent with the 3D reconstruction results. [ABSTRACT FROM AUTHOR]

A controlled acidic precipitation is reported for the direct synthesis of nanosheets self-assembled hierarchical tungstic acid microspheres, and their annealing-dependent thermal conversion into WO3 microstructures is studied for the first time. The synthesis was carried out without the use of any structure directing agents and hydrothermal conditions. The microspheres were found to be consisting of many single-crystalline and highly oriented nanosheets that were hierarchically self-aggregated in spherical form for the minimization of surface energy. An experimentally validated time-dependent formation and growth mechanism was proposed for the development of microspheres. The characterization results indicated that the morphology-preserved thermal decomposition of H2WO4 into WO3 microspheres occurred at 400 °C, whereas a morphology distortion was noticed for the sample synthesized at 600 °C. The increase in annealing temperature further increased the crystallinity of WO3 without changing its monoclinic crystal structure. However, it has a diminishing effect in the specific surface area, pore size and pore volume of the annealed samples. Moreover, the adsorption of methylene blue in aqueous medium was carried out to evaluate its potential environmental application. The WO3 microspheres synthesized at 400 °C showed high adsorption capacity (63 mg/g) compared to the same at 600 °C (56 mg/g). The high activity could be ascribed to the synergistic effects of high surface area, low particle size, porosity, specific morphology and more negative zeta potential. The adsorption further followed pseudo-second-order kinetics with a best fit of the experimental and theoretical values. [ABSTRACT FROM AUTHOR]

Ag sinter joint is gaining greater attention for use with wide-bandgap die attach modules in high-temperature applications. In this study, we have investigated both the necking growth of Ag grain and the mechanical properties of sintered Ag with different Ag particle shapes in a low-temperature, pressure-less sintering process in air and N2. The necking growth ratio of Ag grains plays an important role in the mechanical properties of sintered Ag. Large necking growth corresponds to stronger tensile fracture strength of sintered Ag paste and stronger die shear strength. Self-generated Ag nanoparticles (AgNPs) with of a size less than 10 nm were observed under an air atmosphere, an atmosphere that produces larger necking growth than does that of N2. In addition, self-generated AgNPs were observed in sintered Ag flake particles specimens. Ag flake particles also lead to larger necking growth than that of sintered Ag spherical particle specimens. Self-generated AgNPs accumulated together due to their high surface energy, thus improving the necking growth of Ag grain and leading to a stronger fracture strength. In addition, it was revealed that both the oxygen element and the grain residual strain of initial Ag particles play important roles in the AgNPs self-generation during the sintering process. This study enhances our understanding of the sintering mechanism of Ag particles and the relationship between grain necking growth and its mechanical properties. [ABSTRACT FROM AUTHOR]

Superhydrophobic surfaces with a high contact angle and a low sliding angle are promising candidates for corrosion resistance. In general, an excellent chemical and mechanical stability is the most critical property for superhydrophobic surfaces. In this paper, we proposed a facile, effective and environment friendly method using a simple solution immersion method to fabricate a superhydrophobic surface on copper mesh. The as-fabricated superhydrophobic surface possessing dendritic rough structure and low surface energy displayed a high contact angle of 155.5°. The excellent anti-fouling and self-cleaning properties were demonstrated. The mechanical stability was also exhibited when it was subjected to an impact by a continuous stream of water. In addition, the excellent chemical stability both in acidic and alkaline solutions and the outstanding anti-corrosion effect were showed in electrochemical test due to the air pockets formed between the superhydrophobic surface and water which can well block corrosive medium. This method is facile, timing-saving and environment friendly, which can play a crucial role in practical industries application of superhydrophobic surface. [ABSTRACT FROM AUTHOR]

A variety of materials with superwetting property are fabricated for separation of immiscible oils/organic solvents and water mixture. However, the complex fabrication process, requirement of sophisticated equipment, and associated toxicity strongly limit the development of the superwetting materials. In this paper, a simple two-step dip coating strategy is demonstrated to prepare polydopamine-octadecanethiol modified 3D porous sponge with superhydrophobic and superoleophilic properties (a water contact angle of 156.8° ± 2.5° and an oil contact angle of nearly 0°) through the combination of enhanced surface roughness and low surface energy coating for separation of oil/water mixture. The as-prepared superhydrophobic sponges possess high porosity (greater than 99.2%), low density (below 10 mg/cm3), and 3D porous network structure, which meet well with the needs for adsorption of the actual oil pollutions. More importantly, in situ continuous removal of oil from oil/water mixture is successfully accomplished via a vacuum-assisted system, even in the corrosive environments including turbulent situation, heat, acidic, alkaline, seawater, and glacial water. The continuous oil collection system could avoid the limit in adsorption saturation effectively. We believe that the superhydrophobic sponge with easy large-scale production, economical, and environmentally friendly characteristics can be a superior candidate for the treatment of oily wastewater and practical oil spill accidents. [ABSTRACT FROM AUTHOR]

Graphene nanosheets prepared by liquid-phase exfoliation tend to aggregate easily and irreversibly in most solvents due to van der Waals forces and high surface energy. This article presents a facile, low-cost and novel approach for the preservation and separation of graphene dispersions by adjusting the temperature and solvent. Using IPA-water mixtures can realize green production of graphene nanosheets, and different physicochemical parameters are achievable by changing the proportion of components. Two valid methods for improving stability were discussed in depth: low-temperature storage as a liquid and as a solid. When graphene dispersions are stored in a liquid phase, agglomeration of nanosheets in mixed solvents can be effectively retarded by strong viscous resistance induced by low temperatures. Frozen powder prepared by liquid nitrogen maintains the nanosheets in a dispersed state and is suitable for long-term preservation in the solid phase in ordinary freezers. Furthermore, rapid separation of graphene nanosheets is a challenging problem that retards industrial production. Flocculation induced by slow freezing can accelerate solid-liquid separation, offering a novel approach to obtain easily dispersed powders. Various patterns could be printed on paper and poly(ethylene terephthalate) by a simple and low-cost screen printing technique using the graphene powder, providing a new platform for scalable, low-cost printing of electronics. Consequently, this scalable and simple strategy can be satisfactorily applied to the preservation and separation of graphene and is expected to extend to other nanomaterials, including MoS2 and h-BN. [ABSTRACT FROM AUTHOR]

POSS-doped organic-inorganic nanocomposites (POSS referring to polyhedral oligomeric silsesquioxane) as a new generation of high-performance materials are of special significance, since they simultaneously possess the high rigidity and stability of inorganic species as well as the desired flexibility, ductility and processability of polymer species. Thus, octa(3-amino propyl) POSS (amino-functionalized POSS, denoted as NH2-POSS) was incorporated into polyamide-imide (denoted as PAI) to obtain a series of NH2-POSS/PAI hybrid composites. The molecular structures of NH2-POSS and NH2-POSS/PAI hybrid composites were analyzed by Fourier transform infrared spectrometry and X-ray diffraction. The impact of NH2-POSS on the thermal stability and mechanical properties of PAI as well as the tribological properties of PAI/PTFE-based (PTFE referring to polytetrafluoroethylene) bonded solid lubricant coatings was investigated. Findings indicate that the introduction of a proper amount of NH2-POSS leads to an increase in the glass transition temperature (Tg) as well as hydrophobicity and microhardness of PAI. Besides, NH2-POSS contributes to reducing the friction coefficient and wear rate of PAI/PTFE-bonded solid lubricant coatings. Particularly, the introduction of 7% (mass fraction) of NH2-POSS leads to a decrease in the wear rate of PAI/PTFE-bonded solid lubricant coating by about 50%. This could be attributed to the increase in the load-bearing capacity and decrease in the surface energy of the polymer matrix coatings upon the addition of NH2-POSS. [ABSTRACT FROM AUTHOR]

Zein, a prolamin of corn, is a bio-renewable resource that can potentially offer alternatives for petroleum-based polymers in many applications. Nanocomposite formation with the addition of silicate nanoparticles (Laponite) to zein films, cast from 70% ethanol solutions, significantly improved the mechanical, thermal and barrier properties. Based on FTIR findings, a mechanism for zein–Laponite nanocomposite formation is proposed, which suggests Laponite nanoparticles bind to zein molecules through Si–N bond formation. Structural characteristics investigated using AFM and TEM confirmed exfoliation of the nanoparticle. The changes in the surface energy of the films were evaluated using water contact angle measurements and showed an increase in surface hydrophobicity. The Young’s modulus and tensile strength increased with nanoparticle concentration. The glass transition temperature increased, and water vapor permeability decreased with only a small amount of Laponite. [ABSTRACT FROM AUTHOR]

When subjected to electron-beam irradiation in a transmission electron microscope, the grain boundary in an α-AlO bicrystal is observed to migrate even at room temperature. The bicrystal is composed of grains with the same normal direction, and thus the difference in strain energy or surface energy between the two grains cannot explain the observed migration. We attribute this phenomenon to an increase in grain boundary mobility by electron-beam irradiation, especially by radiolysis effects. [ABSTRACT FROM AUTHOR]

Cellulose nanopaper consists of a dense fibrous self-binding network composed of cellulose nanofibres connected by physical entanglements, hydrogen bonding, etc. Compared with conventional printing paper, cellulose nanopaper has higher strength and modulus because of stronger fibres and inter-fibre bonding. The aim of this paper is to investigate the fracture properties of cellulose nanopaper using double edge notch tensile tests on samples with different notch lengths. It was found that strength is insensitive to notch length. A cohesive zone model was used to describe the fracture behaviour of notched cellulose nanopaper. Fracture energy was extracted from the cohesive zone model and divided into an energy component consumed by damage in the material and a component related to pull-out or bridging of nanofibres between crack surfaces which was not facilitated due to the limited fibre lengths for the case of nanopapers. For comparison, printing paper which has longer fibres than nanopaper was tested and modelled to demonstrate the importance of fibre length. Buckypaper, a fibrous network made of carbon nanotubes connected through van der Waals forces and physical entanglements, was also investigated to elaborate on the influence of inter-fibre connections. [ABSTRACT FROM AUTHOR]

We present a facile, low-cost, and fast method for preparing superamphiphobic surface with water contact angle and rapeseed oil contact angle of 160° and 153° on steel substrate. The fabrication process is composed of the phosphate, Cu co-deposition in phosphating bath and the low surface energy materials modification by 1H,1H,2H,2H-peruorodecyltriisopropoxysilane (FAS-17). Contact angle measurement, X-ray diffraction, scanning electron microscopy equipped with energy-dispersive spectrometry, X-ray photoelectron spectroscopy, and electrochemical workstation were carried out to investigate the surface wettability, chemical composition, morphology, and anti-corrosion performance. Results show that the optimal CuSO·5HO concentration for the surface to achieve superamphiphobicity is 6 g L, and the prepared surface exhibits excellent mechanical abrasion resistance on 600 grit SiC sand paper. Moreover, the dynamic frosting-defrosting experiments indicated that the surface has a good anti-frosting ability. The potentiodynamic polarization proves that the superhydrophobic surface can protect the steel substrate from corrosion solution. Meanwhile the surface also shows a good chemical stability under different pH values and excellent self-cleaning ability in both muddy water and lubricating oil. [ABSTRACT FROM AUTHOR]